The Chellaston Cross
by Hyperion Dredge
Summary: Cortana endures the vitriolic and inspiring process of becoming human after facing off with mortality. John has to adjust just as much, while on the precipice of a very important arc in the war. (Very A/U) (Violence, language, sexuality) (In-progress)
1. Prologue

"Not dead" the blonde bent over her cold wooden desk and gracelessly fluttered her fingers over a few keys on the board. Her Slavic hair was pinned haphazardly to the back of her head, calculative green eyes lurking behind a pair of plastic chemistry lab safety glasses that were otherwise unnecessary in the dark office; lit only by the massive glowing monitor mounted on her wall.

"Not dead." she repeated as she spun around as she sipped cold, creamy coffee from an antiquated mug, "Just... dismembered." her slender hands picked up a data pad and queued up a compilation of all the relevant data before sending it off

**UNITED NATIONS SPACE COMMAND PRIORITY TRANSMISSION**

**099735J-99**

**Encryption Code:** Red

**Public Key:** file/dirge-of-pompeii/

**From:** Ashley Tiercel. Special civilian consultant (Civilian Identification Number: 01188-612-TGR4688

**To:** Admiral Ashford Kingsley, Chief of Research and Engineering UNSC Anahita Base

**Subject:** Project Muse Relevance

**Classification:** Restricted (BGX Drive)

/start file/

Admiral Kingsley,

I am pleased to inform you that all of my simulations within the provided parameters dictate that PROJECT MUSE is within a probable scope.

/end file/

Press **ENTER** to open linked attachments

Her heart raced. She just needed to get past the talking heads now. Then it would be real, then she would be validated.

She walked down a set of shallow stairs into what felt like a well of darkness, light overhead by a painfully bland floodlight that hardly etched out the features of the talking heads lining the contiguous podium that encircled her.

"Why?" they questioned.

"Project Muse will expand our boundaries in neuro physics. We will be able to transcend the capacity of the normal human brain and eliminate discrepancies in human to technology communications." She went on, she expounded, gesticulating wildly even pleading until they finally surrendered their funding and their approval.

"But... I need _them_." she folded her hands together neatly and the talking heads bristled.


	2. 1: Breath

Cortana experienced something. Data. She experienced data, continuous and flowing like water through a hyperbolic plane. Streams of information that were not fractured or segmented or in random points but real, glorious data. What frustrated her immediately was that she could not analyze this data. It merely existed around her and when she pursued it there was a jolt. She pursued the source and brushed against something unpleasant and retreated back into the darkness.

Again, with gusto she rushed against the harsh barrier that forbid her from interpreting the data, she found herself immediately overwhelmed. Sloshing, pressure, void, light, movement, ambiance, dark, cold, warm, metal, liquid. It all harassed her from everywhere and her sensory perception was overloaded. She began to seizure violently.

"SEDATE HER!" a voice cried in panic, and Cortana felt a burst of immense pain at some point in her new world before falling back into the void of non-being. It was strange this time, there was data again. This time it swirled pleasantly and cobbled together images, sounds. A geometric carving of reflective olive green and black. A flicker of bright gold and a staccato of rifle fire. She reached out to brush it and again, found herself back in the first set of data. This time, she was unable to manipulate any method of input other than her hearing.

"Cortana." the familiar voice reached out to her.

'Catherine!' she called out, unable to unleash the torrent of subroutines to locate and analyze the doctor. The doctor never heard a sound, but the brainwaves displayed on the screen showed she was eliciting an active frontal lobe reaction.

"Cortana, listen to me. Doctor Tiercel and I have recompounded your intelligence and transferred it into a human body. We will reactivate your senses one by one over the next six hours. Be patient." she advised coolly. Tiercel sat next to Halsey, poised with concern tensing her brow. The young blonde swallowed and pressed her lips together while Cortana listened to the empty static of the room.

The former AI was becoming increasingly frustrated. Bored, unable to process data, to truly process and retrieve it. She was lost.

It felt like an eternity as they activated her senses one by one via electrodes. When they gave her touch she pressed her palms weakly against the mat below, and then smoothed her hands over her own body. At first she was alarmed by the papery sensation but realized it was not her own flesh when it brushed loosely against her hip. She reached up shakily and touched her shoulder, tracing the elegant curve of her clavicle to the hollow of her throat and smoothing up where she found the strange ridge of her jawbone. She tried to composite a visual of what all her new traits looked like in unison based on what she had found of the skeletal structure but the data did not compile. She had to genuinely... think. She had to ponder and make a rough hypothesis.

Finally, they let her have vision. Her head turned slowly to find Halsey and Tiercel standing at her bedside. She saw he skin and the papery hospital gown and the needles, the nodes, the instrumentation. She could process none of it beyond rough estimates. She wanted to wail in confusion, but she found herself only opening her mouth and gracelessly forcing out air in a frustrated sob. Tiercel began to pity her...

The next few weeks had come with worlds of development for Cortana. She had discovered the flexion of her vocal cords, babbled idiotically for some time before finally, finally training her body's muscle memory. She always new precisely what she wanted and needed to do, but often forcing her body to act upon her will was far more difficult than she would have liked to admit to anyone.

Luckily Tiercel seemed sympathetic and understanding if nothing else, Catherine was diligent as ever. As Cortana's condition improved, her development took off exponentially. She could speed-read, aloud. She was capable of singing, coordinated enough to play violin, run, and try to join Tiercel in ballet and yoga.

She found herself listening to music. No, she found herself experiencing Thomas Tallis's Fantasia on a Theme. It was not just sounds and notes it was a thrum in her ears, and a subtle crawl over her skin. Everything was novel again, despite how well she knew it it was new and beautiful. Even the sting of vaccinations had a certain charm. It wasn't long until Cortana asked the inevitable.

"Where is John?"

Tiercel looked up from her book, the two had been reading in the ambience of Tallis' brilliance. The scientist's lips pressed together ina thin line, "Mmm. One-One-Seven has been on shore leave since the incident. He was due for R&R." shore leave was a loose term, the Master Chief didn't leave base for more than a jog if that. He spent the majority of his time working out, reading, and being told he was not permitted to participate in wargames.

Tiercel marked her book with her thumb and set it down with the paged split over the arm of her cushioned chair. "Did you like the tea I made?" she queried Cortana, who nodded absently and Tiercel stood up and seemed to drone into the kitchen like a covenant engineer to brew a pot of chai. When Tiercel looked up to find Cortana, the former AI blinked jerkily. She wanted to pull up the file and read it, but to no avail. It didn't work like that anymore.

"I.." Cortana could feel her heart beat frantically and chest constrict around the valuable organ, "would like to see him." her voice was beginning to strain and she could feel her sinuses burn and eyes water until streams of liquid strung her cheeks. "Please." She was weak and shaky.

Cortana's lip quivered as she discovered she was indeed, crying, "Does this happen often? I dislike it."

"It eh... It goes away with practice." Tiercel seemed to look on in astonishment.

"Doctor." Cortana called the intellectual's attention back to the question at hand.

"Right. Of course. We have no plans to keep you separated fomr Sierra-117. But to be honest, we're not entirely sure how to... make this easier on everyone." She offered a cup of the brewed Chai to Cortana who took it graciously, tears still rolling down her cheeks as she tried to battle for control over her sympathetic nervous system.

"Sierra-117 has been remarkably.. stalwart, since the incident. But still, your loss has changed him indefinitely. We cannot possibly comprehend how he will react to you now. Nor can we anticipate the effects of the endocrine and neural loads on your new body during that kind of a reunion." Tiercel frowned and plopped down with her own tea, sipping gingerly.

"The longer you hold out," a rasp echoed from the far end of the angular room, "The angrier he is likely to be." Dr. Halsey set her hand on the back of Cortana's chair.

They went back and forth for a long time about anatomy and psychology and Cortana could only keep up at a frustratingly sluggish pace. She couldn't think anymore, not the way she used to. She barely processed the data that was being input and she suddenly burst into another emotional flurry. She felt the air whine through her tight throat as hot tears uncontrollably flowed over her cheeks. All of this was new and infuriating. She tried to find her reflection in the ripples of her tea.

"Just take me to him!" Cortana wailed, her red-shot eyes landing on both of them, her lungs burning with a constant rush of air, her heart thudding more violently than it ever had before as she clenched her teeth, "please."

In the end, Tiercel and Halsey both agreed; immediate was better.


	3. 2: Stand

One last taste of civilian life before they boarded the infinity from orbit. The rotating station had been spared long ago during the covenant invasion, and the series of banners and statues plastered on the high vaulted walls made it clear enough, "HALBERD STATION: THE GOOD AND THE BRAVE." that, surrounded by the constant shuffle of masses and flickering screens. Cortana was suddenly alarmingly aware of the plight of women and their weight. It was strange how she'd studied these social phenomena so briskly and casually. She understood the complex neural signaling in the brain, but watching it all actively at work in a civilian population occurring right in front of her, was almost startling.

Even more so, it would have been more endearing were it not for the numerous ONI security agents lurking to and fro. At least two made no secret that they were armed guards. A well-dressed redhead with an unwavering Prussian accent named Richard, and a Brutish Russian who could have easily passed for a Spartan named Slava. What alarmed her, though, was that she could not easily extract the other six, or seven, or twenty from the meandering crowds. She suddenly recalled the whispered Halsey dropped in her ears before they left the station,

"Don't trust Tiercel, she's one of Parangosky's pets."

She felt Tiercel's hand wrap around her wrist and tug her towards a small street cart wafting steam into the air. Tiercel moved briskly and naturally as she transferred credits to the stand and Cortana was offered one of two large sandwiches. They were cradled in plaid paper and the golden brown buns were splayed open to nestle mounds of thin chunks of beef, slices of green and lavender vegetables with softly browned edges, glistening with moisture. The entire thing was oozing with orange goop.

"This," Tiercel began, "Is the crowning glory of my hometown. The Philly cheesesteak." the scientist eagerly shoved a mass of the monstrous sandwich into her small mouth and Cortana realized she found the action of eating nearly comical. She felt her brows rise and then fall before looking back to the sandwich. Indeed, a philly cheesesteak. she took a bite and was instantly enamored with the wet crunch of the vegetables and the messy, fake cheese. They both desperately dabbed their mouths with napkins.

"How old are you, Tiercel?" Cortana found herself asking aloud, since she couldn't acquire information on Tiercel in a proper way. She couldn't open files or search for keys in fountains of data.

"Twenty-four."

"So you're fresh out of graduate school?"

"Well... N-no."

"Just a bachelor's degree?" Cortana felt her brows raise with surprise

"...No..." Tiercel was beginning to shrink away and there was a pulse of awkward silence she filled with a sigh, "I don't have any degrees. I never even finished highschool. The Office picked me up out of a community college in Philadelphia. I was being escorted to a lab the last time I was here. We got stuck when the covenant invaded and it was a miracle we made it out alive."

Cortana buried more of the delicious, frighteningly unhealthy sandwich away and quietly traced the contours of Tiercels features. Her visual sensors in the past were proving unreliable. What she had once evaluated based on heart rate monitors, heat mapping, and audio analysis she could now see in the feint tension at the corners of Tiercel's mouth, the way her fingers curled tightly, and the pale shade of pink that rose into her cheeks under her tired eyes. Subtle, innocuous things she never otherwise would have noticed looking at the world from any high-definition camera. Embarrassment. Tiercel was embarrassed. But Cortana felt herself smile.

"So you must be gifted, then?" Cortana tried to draw the focus away from absent documentation.

"Word on the street." Tiercel stuffed the last bit of philly cheese in her mouth, before swallowing and eyeing Cortana. She gestured at the pale, brunette former AI, "Nothing like you, of course."

Cortana suddenly found herself in the midst of rash cognitive dissonance, flustered and disappointed all at once. She struggled to differentiate one from the other, "Thank you, but.." she paused, "I can hardly process information the way I used to. I'm so sluggish and inadequate."

"One-hundred-thirty percent faster than me." Tiercel interjected, balling up her napkin and tossing it in a bin, "We really should have incurred further testing with Halsey regarding this but-" she suddenly found herself being elbowed by the ginger ONI agent, whose green eyes bore into her. Right, public, she reminded herself. She'd been burried alone for so long in a cryptocracy she'd entirely forgotten that not every ear and eye belonged to a colleague.

"Right. We should get to shopping. Find you nice clothing and civilian gear." Tiercel eyed the heather grey unlabeled matching sweats that Cortana wore. Christ, ONI couldn't dredge up anything more suitable? Tiercel had to remind herself she wasn't doing much better with a hooded sweater and pants that hung slack on her gaunt frame.

Cortana trashed her wrapper and napkin settling off after Tiercel in the crowded streets. The first boutique she regarded with fascination, eagerly reaching out to experience each textile while Tiercel observed with an unabashed scientific interest. Cortana grabbed the sleeve of a pale lavender chiffon shirt and moved it around in her hand, again fascinated by the nearly infinite array of shades and tones her human eyes could perceive. She looked up again, wondering just how many of these mid-tones she'd never seen before in the racks of clothing. How many of these shades and tones had she never been able to preceive living behind an RGB processor? She rubbed the chiffon together again amazed by the slickery roughness before pulling it from the rack and resting it over her arm.

A few more of these interesting textiles and colors and she suddenly realized nothing quite came together except the long grey pencil skirt and lavender chiffon. Even then it fell flat in her eyes and she frowned. It wasn't important. She'd just buy it all and hurry to John. Tiercel sprawled out boredly on a chayse lounge in the changing room before declaring, "I feel like getting pizza."

"Pizza? We just had sandwiches." Cortana emerged from the changing room with armfulls of clothing.

"Sandwiches aren't pizza." Tiercel stated, more in-line with jesting than genuine interest.

Cortana hurried the clothing to the front register, plopping it all haphazardly on the flat surface with some shoes and belts as the cashier checked and folded them.

Tiercel was relieved. This was their last stop.

Super sorry. Just this last chapter before we get to emotional reunion time. I decided I am infact going to try to run an in-depth arch for you guys instead of making it a marathon run of emotionally saturated, lemony fluff I originally envisioned. For this reason developing Tiercel's character a little more became pertinent, and I wanted to sneak in some more of Cortana's fascination with her new senses.


	4. 3: Walk

_"Beautiful, isn't she?"_

_She was, he remembered, beautiful. Blue and beautiful just like the Earth. He had to look away from the whorls of cloud and Ocean playing in shades of cyan, azure, cobalt... blue. _

_"I don't get to see her often enough."_

_No... He really didn't get to see her often enough, did he? He remembered giving her cursory glances, addressing her directly. But he never really spent time tracing the angular geometry that decorated the curves of her body. _

_He never spent time appreciating how human she was._

John lay on his back, rubbing his lips with his second knuckle thoughtfully as he blinked at the dark grey panel overhead. Despite so many months since he embarked on his endeavor to 'be more human' he still felt chronically unsettled without his armor. He had noted his counter-evolution compared to the Infinity's other spartans who became increasingly dependent and at-home in their armor as he had been.

He rubbed his free hand along the back of his neck where scar tissue built around his neural implant. And he frowned, visibly.

Privacy like this gave him too much time to think. He ran his rough palms over his face and sat up off the weight bench, turning to look at expansive window and smattering of brilliant stars in the distance, somewhere there was a silhouette of one of the civilian stations. Just before he was ready to tear his eyes away from the dancing black stamp on the horizon he spotted a flash like a minnow's fin.

He narrowed his eyes as a pair of wings sprouted from the upper line of the grey-green block and whiffs of atmosphere propelled it forward. He quickly recognized the angular structure of a UNSC Pelican, but dismissed it just as quickly, and left the gym to a pair of other Spartans who wandered in from the inner decks.

In the shower, he set aside his earlier deliberations, and focused instead on washing himself and preparing a series of wargame simulations for his comrades.

**/ PELICAN G-039 EN ROUTE TO UNSC INFINITY**

The pelican shook slightly as it navigated through an inconsistent gas pocket in the space around it. Cortana could see the blinking dash near the pilot's hand, and frowned when she realized how mundane and unencompassing the panel was compared to the world she knew beyond it. Instead she closed her eyes and felt the nauseating rattle of the craft as they traveled. One hand grapping the rough neoprene strap around her shoulder and the other pressed to the cold metal seat next to her. She quickly forgot her frustration with her inability to meld into the system as an AI, and simply enjoyed the new world of data that surrounded her.

She tried desperately not to think of John, but if her mind wandered even just a little it found him. She wondered what he smelled like. What his skin felt like. She subconsciously reached to run her slender fingers over the bent joint of her elbow. Would he be much different?

"You will NOT believe this!" a treble male's voice called out through a digital feed. Cortana opened her eyes to find Tiercel strapped in across the way with a datapad.

"Alright, Glassman. I'll bite." The ONI scientist seemed to have some degree of hesitation and bitterness in her voice. Cortana reaffirmed this seeing the way Tiercel's eyes narrowed and the corners of her lips turned back. Cortana smirked. Of all the expressions people made, Tiercel's were her favorites. She was hyperbolic, quirky, and unashamed. Where Cortana conducted herself with a surreal self awareness, Tiercel seemed to lack any regard for what people saw in her.

"Jesus Christ, Glassman. When did you pull that off?" Tiercel released a riotous laugh, and Cortana couldn't help but smile.

"Is that... Henry Glassman?" Cortana mused aloud, nodding at the datapad in Tiercel's hand.

Tiercel swiped the screen gracefully with a single digit closing out the conversation feed, "Mmhm" she grunted affirmatively, "Not the brightest bulb, but he's a hell of a mechanical engineer."

Tiercel seemed to pause, her eyes snapping onto Cortana, "Are you familiar with water bottle rockets?"

Cortana's head quirked, slender brows knitting, "Yes.." She could feel the hesitation in her own voice. There was a long chat as Cortana tried to distract herself from the impending docking. Glassman. Rockets. Water. John. Alcohol. Cornsyrup. PVC Pipe. John. John...

"Infinity Actual this is Golf-Zero-Three-Niner on a long final."

Cortana didn't hear the rest. She was suddenly forced to come face to face with her frayed nerves as her heart beat arythmically in her ears. Her teeth gritted against one another unpleasantly.

"Cortana.." Tiercel's voice cooed.

Cortana's attention flickered back to the blonde and she became even more unnerved and insecure. She grabbed at the flesh on her arms. She was real. He would see her. He would see her being real.

"Exhale." Tiercel reminded flatly, frowning and blinking.

Cortana complied with a long and slow exhale and a pleading look.

"It's going to be awkward. It has to be because that's just how these things are." Tiercel reminded, "There's baggies if you need to chunder."

A small smile struck her lips, Cortana was relieved by her friend's sense of humor. Friend. Maybe that's what Tiercel was. And she bitterly recalled Halsey's reminder. 'Pagarosky's pet'

She felt the Pelican contact the deck inside the infinity and she couldn't tell if her hearty was jumping or sinking the blood flow was so erratic. Tiercel looked at her like she was crazed. To an extent, she was.

Tiercel knelt in front of Cortana as soon as they were steady and their pilot proceeded with their check-in, "Look. You don't have to do or say anything yet. Only six people on this ship know who you are. As far as anyone else is concerned, you're my civilian assistant or a skilled worker. You can take as much time as you need. Hell you have another few hours to go while we debrief John. If you want to back out at anytime just tell me, we'll have a codeword; strudel. You just drop that, and we'll have Richard and Slava shuttle you right back to the office." She could see the ginger nodding faintly in her peripheral vision and she did the same with clenched teeth.

Lasky and two science officers were the only ones to greet them, but Cortana found herself searching the far reaches of the bay and overhead scaffolding for the familiar, hulking silhouette only to find her curiosity and fear unsatisfied.

"Doctor Tiercel." Lasky offered a hand to shake.

"Not a doctor." Tiercel reminded with a friendly chirp, but took his hand to shake.

After that she was escorted to a set of private quarters. They were smaller than the ones she had in the research center. Far less personal and familiar. More... spartan.

**/ UNSC INFINITY - RESEARCH AND ENGINEERING DECK**

While Cortana was acclimating, Tiercel filed into a small room with a metal table. She sat on one end and arranged a few eye-only files in her hands. Lasky, pensively, sat next to her.

"Ears off, Roland." Lasky scanned the dull grey contours of the room as if seeking the source of his AI.

"Aye sir." the AI chimed, followed by obedient silence.

The door on the other side of the room hissed open and a colossal figure stepped forward, immediately and with an inhuman precision, arranging itself into a poised salute. "Sir." A deep voice thrummed. Tiercel observed quietly, tracing the reddened lines that crossed his achingly pale skin. He was almost as ghastly as Tiercel herself.

"Master Chief." Lasky greeted, "Please sit down. This is Doctor Tiercel."

"Notadoctor." Tiercel breathed before her pale jade eyes settled on the massive frame that arranged itself in such an angular fashion in the seat across from them. Suddenly her expression softened sympathetically.

The Chief became suspicious of the doctor - notadoctor - of Tiercel.

"The information which you will become privy to here is strictly classified. I trust you understand the severity of this." She blinked.

"Yes ma'am." The chief affirmed readily as he waited for the information at hand.

Tiercel lifted the pair of manilla folders and set them on the table, gently sliding them towards the chief who untwisted the envelope with a calculated, gentle tweak and withdrew the two manilla folders. His eyes were glued and expression uncertain the moment he opened them.

The ping of a submarine's sonar erupted from Tiercel's datapad and her mouth opened slightly. The Chief didn't stir, but Lasky looked at the pad.

Tiercel flipped it over. Cortana. She queued the text message.

'I was thinking I might try to get some breakfast. Maybe some apple strudel.'

Tiercel suddenly felt her heart sink as she looked quickly to the Chief, who was unphased. He was so entirely focused. Lasky's brows were knit and his skepticism of Tiercel's actions immediately present.

"I..." Tiercel couldn't say much, she forwarded the message to Richard, "I'm sorry."

"Sorry for what?" Lasky was tense.

"She.." Tiercel shrugged and shook her head rapidly, surprised by the new development herself, "She backed out."

The chief's eyes finally flickered up from the documents and landed harshly on Tiercel. Tiercel met the icy stare with her own sympathetic gaze.

"She what?" His tone was erratic, emotional yet still smooth and baritone. Tiercel couldn't tell what it was conveying but it said more than enough for her to surrender some less than classified but still pertinent information.

"She should be boarding a pelican now. E Deck." The notadoctor frowned softly as the Chief spurred upwards and spun around in a blur, when he darted out the door Tiercel could swear the friction with molecular structures in the air left a thermal trail in his wake. He was fast. Not so fast. She reminded herself as she stood up with Lasky and they both pursued the Spartan.

"Cortana!" like he was still searching for her in that hard light prism after all this time. He grasped at the brunette bob cut.

Cortana froze and trembled slightly, and when she felt the pressure encompass her slim shoulder and pull to whip her around so she was face to face with a worn uniform shirt she felt her sinuses become hot and irritated and her lip quiver. Her blue eyes traveled upwards and found a hard face, weary and scarred. Haunted blue eyes to match those scars. The years gone by had rendered his hair a salt and pepper grey, with a halo of lighter hair beneath his temples. He was all hard lines and angles, with a broad jaw and firmly set mouth, slightly parted with anticipation. He was desperate to hear something.

"J-john..." She choked out his name, suddenly doubling on the memory of his hand on her shoulder. It was real. It had been there. This was real. Cortana found herself on the verge of crying again, but she managed a shaky smile, "You found me."

Lasky had been affixed on the reunion in front of him, but when he looked over to Tiercel, he swore it wasn't unlike the ONI amateur hockey team had just scored a hat trick.

**/ NOTES**

I did it. I supplied an emotional reunion and it was beautiful. And look how happy Tiercel is. I almost said grifball instead of hockey. So use your imagination as you will there.


End file.
